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From: "David Doria" <daviddoria@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: log with syms variables?
Date: Thu, 21 Feb 2008 14:39:02 +0000 (UTC)
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if i do this

syms a b;
simplify(log(a*b))

i get log(a*b)

if i do this:

syms a b positive;
simplify(log(a*b))

i get log(a) + log(b)

The later is what I would like.  Is it necessary to declare
the symbolic variables as 'positive'? Or am I doing
something else wrong?

Thanks,

Dave